Aerofoil



May 22, 1928. 1,670,852

H. D. FOWLER AEROFOIL Fil April 22, 1927 e Sheets-Sheet 1 Ely- 1 a) a -et w/r/msszs INVENTOR' Wzawft .Z'arZ4 7 2 Javi May 22, 1928. 4 1,670,852

H. D. FOWLER AEROFOIL Filed April 22, 1927 e Sheets-Shejet 2 ANORNEY May22, 1928. r

H. D. FOWLER AEROFOIL Filed April 22, 1927 e Sheets-Sheet 3 IN VEN TORWUBW . 1,670,852 H. D. FOWLER v AEROFOIL 5 Sheets-Sheet 4 Filed April22, 1927 INVENTOR JerZan 0Q), Jaw/[9r ATTOI CNEY May 22, 1928. 1,670,852

H. D. FOWLER AEROFOIL Filed April 22, 1927 6 Sheets-Sheet 6 A um 4a 28%Fig; 10

. of the operator for varyin Patented Maize, 1928.

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Application filed April 22, 192'!- My invention relates to aircraft andespecially to the type of aircraft embodying one or more aerofoils oraerial supporting and lifting planes or wings having upper and lowersurfaces which are or curved togive the required lift, the latterordinarily depending on the speed of the craft, power of the motor orother conditions.

7 The principal object of my invention is to provide, in conjunctionwith such aerofoil, novel and efiicient means under the control thearea, camber and angle of inci ence thereof and incidentally controllingthe aspect ratio and movement of the center of pressure. The

v arrangement enables the speed of the craft to be changed and regulatedat the will of the aviator and thereby provides for a low and safelanding, and launching speed.

Another object of my invention is to pro vide means under'the control ofthe. operator which may be used as an auxiliary stabilizer and elevatorcontrol surface, thereb greatly increasing the longitudinal controlabilityof the craft. i

Still another object of my invention is to provide means under'thecontrolbfthe operator for increasing the lift ateither' end of theaerofoil independently;of; the other end thereof, thus greatlyincreasing the lateral controllability ofthe craft;

These objects, and other advantageous ends which will be describedhereinafter, I attain in the following manner, reference belilng1 had tothe accompanying drawings in w 10 Figure 1 is a topplan view, partlybroken 7 away, of an aerofoil embodying my invention, and v v Figure 2an enlarged cross sectional view, taken substantially on line 2-2 onFigure 1, biit showing the auxiliary wing disposed v under the trailingedge of the main wing.

Figure 3 is an enlarged cross sectional view taken on line 3-3 on Figure1, and

Figure 4 an enlarged view, partly in sec-' taken substantially online.44 on Figure 3; the covering of the auxiliary wing being omittedfor the sake of simplicity.

Figure 5 is an enlarged fragmentary top plan view, taken substantiallyon line 5-5 on Figure 3, and

Figure 6 a fragmentary sectional view taken on line 6-6 on Figure 5.

usually cambered.

iline 88 on Figure 7; I

Figure 9'. view taken on line 9-9 on chord,

aerofoils regardless of their camber, chord wing.

' surface of Figure 7 is an enlarged fragmentary view, takensubstantially on line 77 on Figure 1, showing a portion ofthefiiperating mechanism.

Figure 8 is a sectional plan view taken on.

and

Fi re 8. a

igure 10 is a view taken on line 10- 10 on'Figure 7, and

Figure 11, a view Fi re 7.

yinvention is. adapted to be applied to or other characteristics and anyapproved of construction may be employed pro viding that the frame ofthe main wing has sufiicient strength and rigidity to support theauxiliary wing area and withstand the thrusts and loads transmittedtherefrom. For the purpose of illustration, I have shown it applied to amain wing 15 having a leading spar 16 and a trailing spar 17 which-areheld in spaced relation to one another by sturdy compression ribs '18,thus forming the main frame of the principal part 19 o the A trailingportion 20', of considerably smaller cross sectional area, is secured toprincipal part 19 in any approved manner and the entire wing 15coveredwith fabric oi veneer 21 supported on' inferior. ribs 22, aseiscustomary in the manufacture of aircraft; the upper surfaceof trailingportion 20 being a continuation of the upper rincipal art 19, while itslower surface is s harply 0 set from the lower surface of principal part19 in order to accommodate an auxiliary wing as will be describedhereinafter.

As theconstruction of 'aerofoils is well known in the art, it is notbelieved necessary to illustrate or describe specific structuralcharacteristics aside from the primary requisites of providing sturdycom resslon ribs and spars; the trailing spar pre erably being preventedfrom turning over by suitable wire cross braces 23.

I have shown trailing portion 20 as being slotted at three-points toaccommodate trol-- ley beams 24 which are secured to trailing spar 17 bflanged castings 25. Each casting 25, w ich is preferab y secured tospar 17 opposite one of the compression ribs 18, is provided with a pairof vertical flanges 26, between which trolle beam 24 is secured andwhich trans er vertical loads taken on line 11-11 on a drum 36 from thebeam to'the spar, and'with a pair of horizontal flanges 27 which stiffenthe beam against lateral movement, as shown in Figures 5 and 6. d

An auxiliary wing 28, which extends substantially the entire length ofwing 15, is movably mounted on trolley beams 24 by means of trolleys 29,each of which consists of a pair of. plates 30, an upper roller 31 andtwo lower rollers 32. Roller 31 is adapt ed to ride on top of beam 24and carry the weight of auxiliary wing 28, while'rollers 32 engage thebottom of beam 24 and hold auxiliary wing 28 against upward movement andagainst canting. The lower part of each plate is notched and flanged andstraddles a beam 33, which runs the entire length of auxiliary wing 28and which is bolted to flanges 30* formed on plate 30. This constructionis plainly shown in Figures 2 and 4.

When auxiliary wing 28 is disposed below trailing portion 20, as shownin Figure 2, its under surface is in line with or forms a continuationof the curvature of the underside of principal part 19 and is adapted tobe moved on trolley beams 24 in the fol lowing manner: An endless cable34 is'se cured to one side of the center trolley 29, passed over adeflector sheave 35 mounted on the outer end of center trolley beam 24,then carried inwardly to a point immediatelyabove the operators'seat andgiven one or more turns around a drum 36 secured to a shaft 37rotatably, mounted in principal part 1.9 and provided with a handle 38by means of which it may be rotated; cable 34 being led over suitabledeflector sheaves 39,

40 and 41 to give'it the required changes in direction. An endless cable34, attached to trolley 29 on trolley beam 24 at one end of the wing, isled over a deflector sheave 35 on the end of the beam, then overdeflector sheaves 42 and 43 and given one or more turns around a drum 36on shaft 37.

An endless cable 34 is attached to trolley 29 on trolley beam 24 at theother end of the wing, led over deflector sheave 35 on the end of thebeam, then over sheaves 44 and 45- and' given one or more turns aroundon shaft 37. The only difference in the above mechanisms being thelength and manner of running the cables and the manner of mounting ofthe drums on shaft 37.

The full intent and purpose of this invention is to increase the liftingpower of a- Wing by so extending the auxiliary wing 28 rearwardly alonga curvature of a radius B, whose point M is situated to trailing spar.17 by a dimension A (see Fig. 3). When moved back until retained by-stop46, auxiliary wing 28 must maintain a definite position relative to thetrailing edge of the main wing, as indicated by the opening C andposition line D, and an. angle E relatively to the main wing, all ofwhich are predetermined from the characteristics of main wing runoutwardly and, as each cable is con- I nected to a trolley 29, thismovement will cause the trolleys to move longitudinally of trolley beams24 and consequently 'move auxiliary Wing 28 outwardly from undertrailing portion 28 or vice versa; a stop 46 being provided at the outerend of each trolley beam for limiting the outward movement of thetrolleys.

Assuming that an aircraft having my in-' vention installed thereon haslanded, it may take off in the usual manner but it is intended that theoperator will move auxiliary wing 28 rearwardly on trolley beams 24,thus increasing his Wing area and, as trolley beam 24 is of suchcurvature that auxiliary wing 28 forms a continuation of the camberedsurfaces as it moves rearwardly, the wing area, chord and/camber areincreased and the craft given greater li'ftin power; thus allowing theaviator to take 0 from a much smaller field or to rise with a greatlyincreased load.

As the craft rises in free flight, auxiliary wing 28 is drawn undertrailing portion 20, thus decreasing the area of the aerofoil with theattending change in camber and angle of incidence, reducing the headresistance andthereby increasing the speed of the craft until theauxiliary wing is drawn entirely under trailingportion 20; at which timethe craft developes its maximum speed. i

In landing, the above operation is reversed, i. e. auxiliary wing 28 isextended until the wing area is increased to the desired extent and thespeed of the craft reduced due to the drag of the extended auxiliarywing. The increased wing area allows landing at a much lower speed thanwould be possible wit-h a normal wing area, and consequently provides amuch safer landing than is ordinarily possible.

My invention may also be used for controlling the craft when in flight.If it is desired to nose the craft over, auxiliary wlng 28 may beextended to raise the trailing edge ed to give material assistance inthis respect.

If the aviator desires to turn to the right,

' mounted on shaft 37 and ing handle 55 secured to its'outerend.

plished in The moving of one end of auxiliary wing.

28 outwardly while the other end remains under trailing portion 20 maybe accoma number of we s. One manner of accomplishing this end is toemploy certain mechanism whereb the drums may be revolved-in unison or te direction of rota- .tion of one of the drums changed from that ofanother and allowing a third drum to remainstationary. By referring toFi ures'8 to 11, it will be notedthat shaft 37 is composed of'a mainshaft 37 and an upper quill shaft 47, which is' rotatably mounted m abearing'48, suitably mounted in the framework of wing 15.. Drum 36 isfixed to uill 47 and drum\36 to main shaft 37, w ile drum 36 is securedto a uill 49 rotatablyaving a gear 50 fixed to its lower end. The lowerend of shaft 37 is'reduced in diameter and rotatably mounted in' abearing formed in a easting 51.

A cam shaft 52 rotatably' mounted in bearings 53 formed on casting51,'1s provided with two cams 54 and hasan operatsecond shaft- 56, alsorotat'ably mounted in a "pair of bearings 53, has a cam 54 secured vtral aperture through which casting 51 and in a bearing 66suitably sethereon and a lever 57 fixed toits outer end. A lever 58 is'fixed toshaft 52 or formed integral with handle 55 and a link 59 connects theupper end of levers 57 and58 respectively. 'It will be evident'thatmoving handle'55 will rotate shaft 52 and the cams 54 fixed thereon and,as link 59 connects shafts 52 and 56,.the cam 54 on shaft 56will berotated in unison with the cams on shaft 52.

A bearingplate 60, provided with a censhaft 37 extends, is disposed oncams 54- and held against rotation .by pins 61 fixed in casting 51.A-bearing ring 62 encircles shaft 37 and is disposed between plate 61and a gear 63"'which is slidably keyed to shaft 37 and separated fromgear 50 by a bearingring 64. While bearing rings 62 and 64 have beenshown, it isunderstood that roller or ball bearings may be employed ifso desired. f

'An idler shaft 65, rotatably mounted in cured in the framework of wing15, hasQa gear 67 fixed thereon which meshes with gear 63 and with agear 68, similar to r @{is also fixed to shaft 69 and meshes 63, fixedto a shaft 69' rotatably moun in casting 51 andin a bearing 70 suitablysecured in'the frame'of wing 15. A gear 71 I with gear 50 on quill,49.

When it is desired to extend auxiliary of the appended claims.

wing 28 for its entire length, handle 55 is pulled downwardly to raisethe cam faces on cams 54 and move plate 60 upwardly and slide gear 63 onshaft 37 until it is out of mesh with gear 67. Continued movement ofcams 54:will cause drums 36, 36" and 36 to lock together due to theaction of clutch disks 72 secured to adjacent faces of the drumsl Now byturning handle 38, all three drums will be rotated in unison as drum 36"is keyed to shaft 37 and drums 36 and 36 locked thereto by the action ofcams 54 forein}: clutch disks 72 against the faces of the adjacentdrums.

When it is desired to extend one end of auxiliary wing 28 anddraw theother end ders' 73, formed by the reduced portion of the shaft, restingon casting 51 while quill 49 will be supported by plate 60, ring 62,gear 63 and ring 64. This will cause the drums to be separated from oneanother and will cause gear 63 to mesh with gear 67. A. Rotation "ofhandle 38 .will rotate gear 63 and drum 36 in one direction and drum 36in the opposite direct-ion through the action of gears 63, 67, 68, 71and 50, while drum 36 remains stationary due' to quill 47 beingrotatably mounted on shaft 37 9. will'be noted that gear 71 isconsiderably thicker than gear 50 so that these two gears do not comeout of mesh, thus making it necessary to mesh gear 63 with gear 67 onlyand this is facilitated by tapering the bottoms of the teeth on gear 63and the topsv of the teethv on gear 67 It is also to be understood thatthe gears are of such ratio that drums 36- and 36 are rotated at thesame speed.

While I have described my invention as taking a particular form, it willbe understood, that the various parts may be changed without departingfrom they spirit thereof, and hence I- do not limitimyself to theprecise construction set forth, but consider that I "am at liberty. tomake such changes and alterations as fairly come within the scope Havingthus described my invention, what I claim as new and desire to secure byLetters Patent is 1. An aerofoil including a cambered normal wingconsisting of a main portion and a trailing portion of substantiallysmaller cross-sectional area, and anauxihary wing adapted to he failedunder the trailing .por-

tion and to be projected rearwardly and downwardly.

2. An aerofoil including a cambered nor and consisting of a main portionand a trailing portion of substantially smaller crossscctional area, andan auxiliary wing adapted to be faired under the trailing portion and tobe projected rearwardly and downwardly while maintaining the stream lineof the upper surface; the under surface being partly .opened at therear.

1 4. An aerofoil including a-cambered normal wing consisting of a mainportion and a trailing portion of substantially smaller cross-sectionalarea, and an auxiliary wing adapted to be faired under the trailingportion and to be projected rearwardly and downwardly on a fixed radiuswhereby the lifting power of the aerofoil will be increased.

5. An aerofoil including a cambered normal wing having upper and lowersurfaces and a trailing portion, an auxiliary wing adapted to be fairedunder the trailing portion, and means for positively projecting theauxiliary wing outwardly and downwardly relatively to the trailingportion.

6. An aerofoil including a cambered normal wing having upper and lowersurfaces and a trailing portion, an auxiliary wing adapted to be fairedunder the trailing portion, and means for positively projecting theauxiliary wing outwardly and downwardly relatively to the trailingportion and for maintaining-t the.auxiliary wing in spaced relation'with-the'trailing portion.

7. An aerofoil including a normal wing having-upper and lower surfacesand a trailing portion, an auxiliary wing adapted to be faired under thetrailing portion with its.

bottom forming a continuation of said lower surface, and means forprojecting and retracting the auxiliary wing relatively to the trailingportion.

8. An aerofoil including a cambered normal wing having upper and lowersurfaces and a trailing portion, an auxiliary wing adapted to be fairedunder the trailing portion with its bottom forming a continuation ofsaid lower surface, and means for projecting the auxiliary wingoutwardly and downwardly whereby its bottom will be disposed at an angleto said lower surface and its top maintain the stream line ,of saidupper surface.

9. An aerofoil for aircraft including a cambered normal wing consistingof .a main portion and a trailing portion of substanauxiliary wingmovably connected to the main wing and normally disposed under thetrailing portion; and means for projecting and retracting either or bothends of the auxiliary wing whereby the lifting power, longitudinalcontrolability and lateral controlability of the craft is increased.

12. An aerofoilincluding a normal wing having a main portion and aslotted trailing portion, trolley beams secured to the main portion andextending through the slots in the trailing portion, trolleys on thebeams, an auxiliary wing secured to the trolleys, and means forprojecting'and retracting the auxiliary wing.

13. An aerofoil including a normal wing having a main portion and aslotted trailing portion, trolley beams secured to the main portion andextending through the slots in th trailing portion, trolleys on thebeams, an auxiliary wing secured to the trolleys, and means forprojecting .and retracting either or both ends of the auxiliary wing.

14. An aerofoil including a cambered normal wing having a main portionand a slotted trailing portion, trolley beams secured to the mainportion and extending through the slots in the trailing portion,trolleys on the beams, an auxiliary wing cured to the trolleys, meansfor projecting and retracting the auxiliary wing; the trolley beamsbeing so cambered that the top of the auxiliary wing maintains thestreamline of the top of the main wing when said auxiliary beam isprojected. Y

15. An aerofoil including a normal wing having a main portion and aslotted trailing portion, beam supports secured to the main portion,trolley beams secured in said supports and extending through the slotsin the trailing portion, flanges on the beam supports for stiffening thetrolley beams, trolleys on the beams, an auxiliary wing secured 'to'thetrolleys, and means for projecting and retracting the auxiliary wing.

16. An aerofoil including a normal wing having a main portion and aslotted trailing portion, a trolley beam secured to the main portion andextending through the trailing portion, a trolley on the beam, a drumro- Inc tatable in the main portion, a sheave on the outer end f thebeam, an endless cable at taehed to the trolley and encircling the drumand the sheave, and means for rotating the drum.

17. An acrofoil including a normal Wing having a main portion and aslotted trailing portion, trolley beams secured to the main portion andextending through the slots in the trailing portion, trolleys on thebeams an auxiliary wing secured to the trolleys, a sheave rotatable onthe outer end of each beam, drums rotatable in the main portion,

an endless cable attached to each trolley" and encircling one of thesheaves and one of the drums, and means for rotating one drumin onedirection and another drum in the opposite direction.

18. In an aerofoil having a main wing, beams secured to the main wing,trolleys on the beams and an auxiliarywing secured to the trolleys;means for moving both ends of the auxiliary wing in unison orin-opposite directions including a shaft. a drum and a driving gearkeyed to the shaft, a quill rotatable on the shaft, a drum and a drivengear fixed on thequill, clutch faces on the drums, transfer gearsmeshing with the driving and driven gears. endless cables encircling thedrums and attached to the trolleys, means for raising and lowering theshaft, and the quill, and means for rotating the shaft.

19. In an aerofoi-lrha'ving a main Wing, beams secured to the main wing,trolleys on the beams and an auxiliary wing secured to the trolleys;means for moving both ends the trolleys; means for moving the upperbearing, a drum on of the auxiliary wing in unison or in oppositedirections including a sleeve rotatable in the main wing and heldagainst downard movement, a drum on thesleeve, a shaft rotatable in thesleeve and in the bottom of the main Wing, a drum and a driving gearkeyed to the-shaft, a quill rotatable on the shaft, a drum and a drivengear fixed on the quill, clutch faces onthe drums, transfer gearsmeshing with the driving and driven gears, endless cables encircling thedrains and attached to the trolleys, means for raising and lowering theshaft and the quill, and means for rotating the shaft.

20. In an aerofoil having a main Wing, beams secured to the main wing,trolleys on the beams and. an auxiliary wing secured to both ends of theauxiliary wing in unison or in opposite directions including upper andlower bearings in the main wing, a sleeve rotatable in the sleeve, ashaft rotatable in the bearings, a drum and a driving gear keyed to theshaft, a quill rotatable on the shaft, a drum-and a driven gear fixed onthe quill, clutch faces on the drums, transfer gears meshing with thedriving and driven gears, endless cables encircling the drums andattached to the trolleys, cams rockable on the lower bearing, a plateresting on the cams and supportlng the driving gear and the quilhmeansfor rocking the cams, and means for rotating the shaft.

In testimony whereof I have signed my name to this specification. i

HARLAN D. FOWLER.

